Science: Fluorine’s Empire

Organic chemistry is about to have a pup, and the pup may grow, theoretically at least, as big as its mother. This week the Minnesota Mining and Manufacturing Co. announced that its plant at Hastings, Minn, is turning out a whole litter of “fluorochemicals”—compounds just like ordinary organic chemicals (e.g., acetic acid, ether, etc.), except that they have fluorine in their molecules instead of hydrogen. It should be possible, says Dr. Nelson W. Taylor, manager of Minnesota Mining’s fluorochemical department, to make fluorochemical substitutes for all the 100,000-odd organic compounds, from TNT to DDT, that chemists have synthesized so far.

Snug Atoms. Organic chemistry deals with carbon compounds like those found in living organisms. Most of them have long chains or rings of carbon atoms with one atom or more of hydrogen attached to each carbon atom. Fluorine atoms are heavier than hydrogen, but they are about the same size, and they fit snugly into the molecule without disturbing the existing arrangement of the carbon atoms. The result of replacing the hydrogen atoms in the molecule with fluorine is a compound which resembles the organic original in some respects. But the new fluorochemical has different and sometimes remarkable properties.

For one thing, fluorochemicals are unusually stable. Unlike the organic chemicals, which are often inflammable or explosive, they resist decomposition by heat, chemical reagents or ultraviolet light. They are not attacked by bacteria or fungi. Some of them are very strong acids, others are so inert that they make fine fire extinguishers.

Magic Cell. Fluorochemicals are nobody’s monopoly, but Minnesota Mining believes it has the best commercial method of making them. Instead of starting with dangerous and expensive fluorine gas, its process, invented during World War II by Professor J. H. Simons of Florida University, uses an electrolytic cell charged with hydrogen fluoride, which is much easier to handle. The organic compound that is to be transformed is mixed with the hydrogen fluoride. When an electric current is passed through the solution, fluorine atoms obediently change places with hydrogen atoms in the organic compound, turning it into the corresponding fluorochemical.

Minnesota Mining is not yet talking about all the fluoroproducts it is making. They are still expensive ($2 to $5 a lb.), but some of them, it hints, may be offered to the public soon. Others will reach the public or industry through chemical manufacturers who buy fluorochemicals and use them in their own products. Some of the products:

PLASTICS. Fluorochemicals link together into plastics just as organics do. But the plastics are wholly fireproof and may turn out to be extraordinarily strong.

DYES. A small amount of fluorochemical in the molecule of a dye often changes its color, giving dye manufacturers a whole new color range.

DETERGENTS. Certain “surface-active” fluorochemicals are more powerful cleaning agents than any yet known.

WETTING AGENTS. A small amount of the proper fluorochemical makes a solution “wetter.” This property is valuable in textile dyeing; it helps the dye reach every fiber of the cloth.

PAINTS AND VARNISHES. The stability of fluorochemicals makes them extremely resistant to weathering.

POLISHES. Some fluorochemicals will not stick to either water or grease. This makes them effective as self-cleaning auto polishes.

DRUGS AND COSMETICS. Because some fluorochemicals are inert, they do not irritate human tissues, may replace organic compounds which the skin cannot tolerate.

Such items are only the beginning, the Minnesota Mining men say. Lost in chemical ecstasy, they look forward to the day when fluorochemicals will double or triple the number of useful compounds that chemists can play with.